Mills C4 1L
Best bloom stimulator for growers seeking denser, more aromatic flower yields.
Mills C4 is an advanced bloom stimulator formulated to enhance nutrient delivery to developing flowers, promoting the maturation of essential oils during early and mid-flowering stages. This predominantly organic formula optimizes nutrient profiles when used with Basis A&B, supporting robust flower initiation and overall plant health. It is compatible with beneficial microbes, leading to quicker fruit set, increased vitality, and denser, heavier flowers and fruits.
$45.00
Owner Satisfaction
4.7
/ 5
Category Rank
50
/ 4425
#50 in Fertilizers
Price vs Category Average
-27%
Below average
Package Volume
1
/ L
Who it's for
- Gardeners using the full Mills nutrient ecosystem
- Commercial growers seeking maximum harvest weight and density
- Connoisseurs prioritizing superior terpene profiles and flavor
Who should skip it
- Minimalists wanting a simple, all-in-one feeding solution
- Budget-conscious hobbyists looking for affordable nutrient options
- Beginners intimidated by precise measurement requirements
Performance breakdown
Bloom Stimulation
Accelerates flower initiation for faster, more reliable crop development.
Essential Oil Production
Significantly boosts terpene profiles and resin density during mid-flowering.
Nutrient Synergy
Pairs perfectly with Basis A&B for a balanced, high-performance feeding regimen.
Microbial Compatibility
Safe for use alongside beneficial bacteria and fungi in the rootzone.
Yield Enhancement
Delivers noticeably denser, heavier fruits through optimized phosphorus and potassium levels.
Ease of Application
Liquid concentrate formula mixes effortlessly into standard irrigation schedules.
Key Specs
Package Volume
1L
SKU
400000004594
UPC
859797002229
Formulation
Predominantly organic
Activity
Zero biological activity
Fertilizer Type
Bloom Stimulator
Fertilizer Form
Liquid Concentrate
Fertilizer Source
Organic
Features
- Advanced bloom stimulation
- Facilitates essential oil maturation
- Optimizes P and K levels
- Promotes quicker fruit set
- Increases oil and sugar production
- Enhances flower density and weight
- Compatible with beneficial microbes
- Predominantly organic composition
What customers say
Customers consistently praise Mills C4 1L for its exceptional quality and outstanding value. Many report powerful effectiveness, observing significant improvements in plant health and robust yields. This reliability makes C4 a trusted component for advanced feeding strategies. Although the initial cost is higher, the concentrated formula provides superior long term value. Growers consider it a wise investment, reliably achieving predictable, high performance results. The product delivers on its promise of quality and effectiveness, making it a worthwhile purchase for serious growers seeking consistent success.
Know before you buy
Mills C4 is designed for the early to mid-flowering stages. You should begin applying it once your plants have initiated flower development to maximize fruit set and essential oil production.
While it is specifically formulated to work optimally with Mills Basis A&B, it is compatible with most standard nutrient programs. Always check your total EC levels when mixing products to avoid nutrient burn.
Yes, Mills C4 is fully compatible with beneficial microbes. Its formulation supports a healthy root zone environment, allowing you to use it alongside your preferred microbial inoculants without concern.
No, C4 is a bloom stimulator, not a base nutrient. It is intended to be used as an additive to boost phosphorus and potassium levels and enhance oil production, rather than as a standalone fertilizer.
The predominantly organic base helps optimize nutrient uptake and plant vitality. This leads to denser, heavier flowers and improved sugar production compared to using base nutrients alone.
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